# -*- makefile -*-
# -----------------------------------------------------------------------
# Intent: Dependency-free macros used to source library makefiles
#         and define the build environment.
# -----------------------------------------------------------------------

$(if $(DEBUG-bootstrap_mk),$(warning ENTER))

##---------------------##
##---]  CONSTANTS  [---##
##---------------------##
is-false = $(if $(1),true,$(null))
is-true  = $(if $(1),$(null),true)

##--------------------------##
##---]  LIBRARY MACROS  [---##
##--------------------------##
is-null              = $(if $(1),$(null),$(error $(1)= is undef))
is-null-var          = $(if $$(1),$(null),$(error $(1)= is undef))
is-null-var-indirect = $(if $(1),$(null),$(error $(1)= is undef))

## variable flavor:
# origin - undefned
# default
# environment
# environment override
# automatic
# null(blah) ?   - true

## -----------------------------------------------------------------------
## Intent: Given an indirect var containing varname of a makefile *_ROOT
##         parent director, derive a *_MKDIR variable and conditionally
##         include the makefile hierarchy.
## -----------------------------------------------------------------------
## Given:
##   o var containing OPT_ROOT=path
## Return:
##   o OPT_MKDIR=$(OPT_ROOT)/makefiles
##   o If exists include $(OPT_MKDIR)/include.mk
## -----------------------------------------------------------------------
# library-include   := $(call mk-library-include,blah)

mk-library-include=$(error revisit mk-library-include)

#$(strip \
#  $(warning mk-library-include: $$1[$(1)] = [$($(1))]))\
#  $(call is-null-var,1)\
#  $(foreach var,$($(1)),\
#    $(info var=$(var) is-null=$(call is-null-var,var))\
#  $(foreach val,$$(var),\
#    $(info val=$(val))\
#    $(foreach makedir,$(subst _ROOT,_MKDIR,$(var)),\
#$(warning makedir=$(makedir))\
#      $(if $($(makedir)),$(null),\
#        $(eval $(makedir)=$$$$($(var))/makefiles)\
#$(warning $(makedir) = $($($(makedir))))\
#$(info $$(wildcard $(val)/makefiles/include.mk) = $(wildcard $(val)/makefiles/include.mk))\
#        $(foreach mf,$(wildcard $(wildcard $(val)/makefiles/include.mk)),\
#$(warning $$(eval include $(mf)))\
##          $(eval include $(mf)))\
# )

$(if $(DEBUG-bootstrap_mk),$(warning LEAVE))

# [EOF]